Remove some seldom used dependencies from pudl-dev environment.yml

[zaneselvans]

The dask-labextension, py-spy, nbdime and seaborn packages are only used occasionally and only by some people, so I wanted to pull them out of the default pudl-dev environment to slim it down a little bit.

[codecov]

Codecov Report

Merging #1615 (3b4557b) into dev (0dd285d) will decrease coverage by 0.0%.
The diff coverage is n/a.

❗ Current head 3b4557b differs from pull request most recent head f479c80. Consider uploading reports for the commit f479c80 to get more accurate results

@@           Coverage Diff           @@
##             dev   #1615     +/-   ##
=======================================
- Coverage   84.0%   84.0%   -0.1%     
=======================================
  Files         65      65             
  Lines       7181    7176      -5     
=======================================
- Hits        6039    6034      -5     
  Misses      1142    1142             

Impacted Files	Coverage Δ
src/pudl/output/eia860.py	65.8% <0.0%> (-0.7%)	⬇️
src/pudl/transform/eia860.py	96.4% <0.0%> (-0.1%)	⬇️
src/pudl/metadata/resources/eia.py	100.0% <0.0%> (ø)
src/pudl/metadata/resources/eia860.py	100.0% <0.0%> (ø)

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